Category: network

How to set up NordVPN on Ubuntu

There are two ways to set up a VPN connection with NordVPN on Ubuntu. The first one is to add NordVPN’s package repository to the apt sources and then install the nordvpn client via a simple sudo apt install nordvpn. The second one is to install OpenVPN and configure it to use the servers of NordVPN.
This how-to was written for Ubuntu 18.04 LTS (Bionic Beaver).

NordVPN setup with NordVPN package repository

  1. Download the NordVPN package (.deb) for Ubuntu:
  2. Install the package on your Ubuntu system:
    sudo dpkg --install ./nordvpn-release_1.0.0_all.deb
    Note that installing this package does only add the NordVPN package repository to apt, no executable is installed.
  3. Install the nordvpn client software:
    sudo apt update
    sudo apt install nordvpn
  4. Connect the nordvpn client (the server is selected automatically):
    nordvpn connect
    The general command to connect has the form:
    nordvpn connect [<country&gt;] [<city&gt;] | [server]
    so to connect to a specific country (and city) the additional arguments must be given:
    nordvpn connect United_Kingdom Manchester
    To get a list of available countries and cities you can query them with:
    nordvpn countries
    nordvpn cities
    It is also possible to give the server name directly:
    nordvpn de442

NordVPN setup with OpenVPN

  1. Install openvpn on your Ubuntu system:
    sudo apt install openvpn
  2. Get the OpenVPN configuration files for NordVPN:
    cd /etc/openvpn
    sudo wget
    sudo unzip ./
    If an error is encountered during the download step above, it may be necessary to install the ca-certificate package:
    sudo apt-get install ca-certificates
    After unzipping there will be a folder ovpn_tcp and ovpn_udp which contain the NordVPN server configuration files for OpenVPN.
  3. Connect to OpenVPN using one of the NordVPN servers:
    openvpn /etc/openvpn/ovpn_udp/
    You will need to enter your credentials for NordVPN.

Extracting MPEG2-TS from Wireshark capture file

When working with IP multicast streams it can sometimes be useful to convert a captured IP stream file to a corresponding MPEG2 transport stream (TS) file. Wireshark has a built-in capability to extract MPEG2-TS packets from the UDP packets of an IP multicast stream. This feature is somewhat hidden away in the menus and not obvious to find.

An IP multicast stream

First select a frame of the UDP stream you are interested in by clicking on it. Then navigate the menu bar to “Analyze” &gt; “Follow” &gt; “UDP Stream”.

Follow the UDP stream

A new window will open, showing the contents of the UDP stream in one continuous flow of data. Now select “Show and save data as” &gt; “Raw” and hit “Save as …”.

Extract MPEG2-TS from UDP stream

Give the new file a name and hit “Save”.

It is also possible to filter out specific parts of the UDP stream, but in most cases the “Entire conversation” is what is wanted.

The result: a plain MPEG2-TS

That’s it! All MPEG2-TS packets have been extracted from the UDP stream and are stored to a separate file. The MPEG2-TS file can now be used for other tasks, like error checks or timing analysis.